Pump lubrication



P 1952 F. D. LOWTHER, SR 2,612,116

PUMP LUBRICATION Filed Feb. 17, 1949 Fig,

Franklin D. Low/her, $1:

INVENTOR.

Fig.2.

Patented Sept. 30, 1952 g lum -Eo --P E OFFICE v LUBRICATION I p MfnanklinbrLowther,Sn,Bellaw.Ya, jApplicationfFebruary 17, imaseriamo. 71,005 f 1 This invention relates to new and useful immovements andstructural refinements in -liquid pumps, more specifically-"liquid pumpsof I the reciprocable piston type, and thep-rincipal object of theinvention is to provide pressure lubrication for the piston'or pistonrod, and at the-same time, to separate the lubricant from the liguidin tl a This object is achieved by the provision of a lubricant chambertogether-with a recipre'cable plunger, the plunger being actuatedbyvariation of pressure in the pump cylinder bore and 'feedinglubricantunder'pressure *to the-piston orpiston rod.

Another important feature of'the invention resides in the provision ofpacking on the piston head, so that the lubricantdel'ivered to thepiston or piston'rod is separated from the liquid being pumped. I

A further feature of the invention res-ides inits simplicity ofconstruction and operation, in'its durability, and in its possibleapplication to various uses, particularly for pumping chemicals, acidsand other'corrosive liquidsi I With the above more important objects"and f-eatures'in view ands-uch other objects andieatures as may becomeapparent asthis specification proceeds, the invention consistsessentially of the arrangement and construction of parts as'illu'stratedin the accompanying drawings, in c V l- Figure 1 is a side elevationalview of the invention including means for reciprocating the pumppiston,-and

Figure 2 is a cross sectional view-of thei-nv'ention per se. a I

Like characters of reference are usedto designate like parts in thespecification and throughout the severalviews.

Referring now to the accompanying drawings in detail, the inventionconsists of a pump cylinder structure designated generally by thereference character 5, the same including a body or block 6 equippedwith a removable head 1 which,

" ,ijoiaim. (01.103-153) l. 1.5 i I2 having iinner and outer ends, theinnerend :of the' 'bore fl' extendinginto the head] andlcommunicatingwith a passage 43.. This passage is provided in the head I and extendssubstantially at right angles to the bore l2, .as will be clearlyapparent.

One end of thepassage 13 constitutesaninlet port 14 while its remainingend constitutes :an exhaust port 15,. both these ports being providedwith suitable, spring pressed checkvalves 1.6, 1.1 respectively whichpermit the flow of liquid through the pump: in only :one direction,namely that illustrated by the arrow 18. a

"The check valves 16, I! are of any conventiona=l type,'= and fluiddelivery and exhaust conduits :19, 20 communicate :with the passage [3for obvious reasons.

A piston 21 isreciprocable in the cylinder bore 12, 'and'the outerend-portionof the latter is counter-bored to receive the usualpackingitretained in position by means of a packing nut 23. The pistonv2| projectsoutwardly from the'bore :12 and may be ofuniform diameterthroughout, or alternatively, may be provided with a suitable pistonrod. In anyevent, the piston .orrpiston rod is reciprocated in the bore[2 in any suitable manner such as for example, by a earn, an eccentric,or as shown-inithe accompanying drawing, by a crank 24 andaconnectingrod '25. Ifidesired, the crank 24 may be mounted 'upon'a crankshaft 2-6journaled-in a suitable bracket 23, the latter being-supported bytheaforementioned base plate M and-the-shaft 2 6' being rotated by apulley and belt-driven. Anyother means for reciprocating thepistonimmay, ofv course, be':employe'd. i'lheessencelof novelty in theinventionres'ides in-the provision of-a lubricant chamber 23 in the body6-, this. chamber communicating with the atoremen tioned passage l3through the medium of'm :openlng' '30providedj-in" the head '1 at oneendofl the lubricant chamber; A lubricant delivery' passagev 31 isprovided at the remaining :end of the chamber-Hand is.in.=.communication with thecylinder bore :12 as' will be clearlyapparent.

lt should benoted thatpthe 'passage' 3 l is covered by th'e piston 21,"but sufficient clearance exists betweenthe piston and :the bore 1-2 tofacilitate flow of lubricant under pressure intothe cylinder 3 tively,the plug 33 being absent when a constant supply of lubricant is providedfor the chamber 29 and the lubricant, after performing its function, iseither discharged or recirculated.

The inner end portion of the piston 2! is provided with further packing34, and if the pump is to be used for chemicals, acids or othercorrosive liquids, a piston head 35 of non-corrosive material may besecured to theinner end of the piston, substantially as shown.

It is to be noted that the lubricant delivery passage 3| and thedischarge passage 32 communicate when the cylinder bore l2 intermediately of the packing 22, 34, that is to say, the

. lubricant delivered through the passage 3| to the I A reciprocableplunger 36 is provided in the aforementioned lubricant chamber 29,

this plunger being equipped with a packing gland31 and also beingprovided with an annulargroove 38. One end of a lubricant inlet duct 39;cornmunicates with the groove 38, while the remaining end of the ductmerges or opens intothe chamber 29, as shown. Lubricant under pressureis forced into the chamber 29 through an inlet port 40 which isregistrable'with the duct 39 upon reciprocation of the plunger, that is,the port 49 registers with the groove 38 and the duct 39 when theplunger is slid toward the .endof the chamber-29 provided with thepassage 31-. v

A lubricant delivery-conduit communicates with the port 40 and a checkvalve 42 is provided so that lubricant may enter but cannot leave thechamber 29 through the port. v 1

Having thus described the constructionof the invention, the method vofoperation thereof will now be presented. a

' As the piston 2| is reciprocated the inlet and outlet check valves 16,I! will alternately open and close, so that the liquid which is beingpumped will be forced through the passage l3 in an intermittent,pulsating manner as in pumps of conventional design.

With reference to Figure 2, while the piston on its working stroke ismoving fromleft to right,

the resultant pressure in. the passage l3 will be transmitted throughthe opening 39- to. the plunger 36 and as a result, the plunger. will beforced from right to left in the chamber 29. As has been alreadyexplained, under such circumstances the'port 40,will r egister with theduct 39 and lubricant under pressure will enter through the bore 40 intothe chamber 29 and thenthrough the passage 31 to the piston in the borel2.-,-- Lubrication of the piston will thus be effected.

. On the other hand, on the return stroke of the piston the resultantreduced pressure in. the passage I3 will draw the plunger 36 from leftto right to the position shown, whereby the bore 40 will be closed untilthe next cycle of operation; It will be apparent from'the foregoingthatan intermittent, pulsating supply of lubricant to the piston 2| willbe efiected, and by .virtue of the packing 34, the lubricant will beseparated from the liquid pumped through. the passage .13.

The plunger 39 may be referred to as an equalizing plunger since byvirtue thereof an equal amount of pressure will exist in the chamber 29and the passage'3l as in the chamber I3. In other words, the pressure ofthe liquid being pumped will be substantially equal to the pressure ofthe lubricant, so that pressure on both sides of the packing 34 willalso be equal. From this it will be apparent that whereas in conven-"tional pumps the packing22 was. employed for retaining the pressure'ofthe pump liquid, the

a correspondingly equal pressure of the lubricant.

Finally it should be added that the lubricant is delivered to thechamber 29 through the conduit 4'! under pressure of another pump (notshown) which is somewhat higher with respect to the operating pressurein the passage l3 and chamber 29, whereby admission of the lubricantinto the chamber 29 is facilitated.

It is believed that the advanatges and use of the invention willbeclearly understood from the foregoing disclosure and accordingly,further description thereof at this point is deemed unnecessary. r I

While in the foregoingthere has been shown and described the preferredembodiment of this invention it is to be understood that minor changesin the details of construction, combination and arrangement of parts maybe resorted to without departing from the spirit and scope of theinvention as claimed 7 Having described the invention, what is claimedas new is:

In av pump, the combination of a body provided with a cylinder borehaving closed and open ends and also provided with inlet and exhaustpassagescommunicating with the closed end of said bore, a pistonreciprocable in said bore, outer packing in the open end of the bore inengagement with said piston, inner packing carried by the inner end ofthe piston, said body being provided with a lubricant chamber. and witha pressure transmitting passage connecting one end of said chamber withsaid exhaust passage, a lubricant delivery duct extending fromthe otherend of said'chamber and communicating with said bore at a point betweenthe first and second packings, a lubricant supply pipe connected to saidlubricant chamber intermediate the ends of the latter and a plungerreciprocable in said chamber and having a solid face'atone end actuatedby pressure from said piston, said plunger having a ported face at theother end and passage means therein for establishing communicationbetween said supply pipe and said delivery duct. v 1 s FRANKLIN D.LOW'IHER, sn.

REFERENCES CITED 1 j "UNITED STATES PATENTS Number Name Date 491,224Poore Feb. -7, 1893 1,813,846 Goldsborough July '7, 1931

